At the present time, there are three ways to manufacture hot-dip coated products.
If stringent requirements are made of the surface quality and of the dimensional accuracy, a cold-rolled strip undergoes recrystallization annealing, subsequently hot-dip coating and then temper-pass rolling and/or stretcher-and-roller leveling.
In the case of similar requirements, a hot strip that has been previously hot-dip coated is reduced to dimensional accuracy on a separate cold-rolling mill.
As the third possibility, in cases when lesser requirements are made of the surface quality and of the dimensional accuracy, a hot strip is hot-dip coated after elimination of the mill scale and then undergoes temper-pass rolling and/or stretcher-and-roller leveling.
According to Stahl-Lexikon [Steel Lexicon], 25th Edition, published by Verlag StahlEisen, Düsseldorf, Germany, pages 134, 139, the term “temper-pass rolling” refers to cold rerolling, that is to say, a slight cold reduction of the strip following a preceding heat treatment or hot working, whereby the thickness reduction amounts to 0.5% to 3%.
European patent application EP 1 203 106 B1=U.S. Pat. No. 6,761,936=WO 01/011099 A2 discloses a method for the hot-dip galvanization of hot-rolled coated steel strip, whereby, in a first step, the strip is introduced into a pickling station, in a subsequent step, the strip is introduced into a rinsing station, then into a drying station, and in another step, it is introduced into a galvanizing furnace and galvanized, whereby the above-mentioned process steps are carried out under the hermetic exclusion of air and oxygen from the environment.